Kisspeptin
Kisspeptin is a hormone acting as a ligand or binding element to a g protein couple receptor related to the stimulation of several biological functions within the human body. Kisspeptin is related to the stimulation of a variety of functions all over the human body. Discovery of Kisspeptin Kisspeptin was first discovered in 1996 in Hershey, Pennsylvania. That is part of how it gets its name because of the candy, Hershey’s kisses, which is manufactured in the town of Hershey Skorupskaite, Karolina, Jyothis T George, and Richard A Anderson. “The Kisspeptin-GnRH Pathway in Human Reproductive Health and Disease.” Human Reproduction Update 20.4 (2014): 485–500. PMC. Web. 19 Feb. 2018. . “The SS in KiSS1 acknowledges that it is a ‘suppressor sequence’ ” because kisspeptin was thought originally only to be associated with the suppression of tumors . Since then, significant research has been done demonstrating how much influence kisspeptin has over numerous biological functions . Structural Properties/Release Mechanism Kisspeptin is a hormone, a "special chemical messenger in the body," that works as the ligand in a g-protein receptor mechanism “What Are Hormones and What Do They Do?” Hormone Health Network, Endocrine Society , 2018.. After it pairs with the g-protein coupled receptor, the receptor, usually KISS1R or KISS1, then activates the corresponding g-protein. Once kisspeptin is activated, several activities that are then stimulated within the cell including, but not limited to : phosphorlylation, movement of calcium, and the release of certain kinases. Kisspeptin is found both in the adrenal cortex and hypothalamus of the brain which are the two regions associated with "sex drive." Functions in the Human Body 1. Puberty Kisspeptin affects the release of GnRH which is the gonadotropin releasing hormone. That is very important because GnRH in turn stimulates the release of gonadotropin which is important for a person’s ability to reach complete sexual maturity and to reproduce. Studies have shown that kisspeptin is able to trigger the release of GnRH from its location in the hypothalamus, which is a site in the brain related to several hormones. "Kisspeptin-mediated GnRH stimulation is sex steroid dependent." Specifically, the research has shown that problems with kisspeptin’s receptor prevent men from reaching full sexual maturity. A study done with female and male mice showed that “mice lacking the KISS1R receptor failed to undergo puberty and mutant males were sterile with very small genitalia and lacked secondary sexual characteristics." Similarly, "mutant female mice also failed to undergo sexual maturation; the uterine horns from mutants were thread-like and the ovaries significantly smaller than normal.” The image to the right shows how the mechanism works for females reaching puberty. However, the study did not suggest that the lack of kisspeptin had a significant effect on phenotypic presentations of gender. 2. Tumor Suppression It most widely known for its ability to suppress the formation of tumors in relation to metastasis, the formation of malignant cells away from the initial growth of cancerous cells. “To date, the metastasis suppressor activity of KPskisspeptins have been identified in numerous cancers, including…bladder, gastric, esophageal, pancreatic, and lung … cancers.”Cvetković, Donna, Andy V. Babwah, and Moshmi Bhattacharya. “Kisspeptin/KISS1R System in Breast Cancer.” Journal of Cancer 4.8 (2013): 653–661. PMC. Web. 19 Feb. 2018.The research shows that “a reduction in KISS1 and/or KISS1R expression has been shown to be associated with poor prognosis in cancer patients” meaning that the patients have decreased chances of surviving the cancer .Further, recent research shows how the kisspeptin is very closely related to breast cancer. The two receptors most closely associated with kisspeptin do not both appear to work in the reduction of the spread of cancer. Recent “studies indicate that KISS1R signaling may correlate positively with breast tumor progression and metastatic potential,” so essentially that means that there are increased rates of breast cancer when kisspeptin binds with KISS1R unlike when it binds with KISS1 . There is still ongoing research to understand how this is possible. 3. Pregnancy Kisspeptin is highly present during the early stages of pregnancy. As soon as the woman gives birth and the placenta is also released from the uterus, there is an immediate drop to pre-pregnancy levels of kisspeptin in the woman’s system. Reynolds RM, Logie JJ, Roseweir AK, McKnight AJ & Millar RP 2009 A role for kisspeptins in pregnancy: facts and speculations. Reproduction 138 1–7. There also several possible reasons why this occurs. It is possible that “kisspeptin plays a key role in… regulating implantation the egg and subsequent development” of the embryo. There is also ongoing research to see if kisspeptin is related to the prevention of ectopic pregnancies i.e., pregnancies that are formed outside of the uterus . Without the further developments in research, it is clear that kisspeptin is very important for maintaining a healthy pregnancy and carrying a baby to term . 4. Kidney Also, kisspeptin is related to proper kidney function. “The present study has shown that expression of kisspeptins and kisspeptin receptor are altered in the kidney tissues of chronic renal impairment, raising the possibility of their pathophysiological roles in chronic renal failure."Shoji I, Hirose T, Mori N, et al. . Expression of kisspeptins and kisspeptin receptor in the kidney of chronic renal failure rats. Peptides . 2010;31:1920–1925 The study was performed using rats as the test subject. The study compared rats with with full kidney function with those with artificially decreased kidney function. Those with the decreased kidney function are those with difficulties concerning the expression of kisspeptin and the kisspeptin receptors. Works Cited Category:Science Category:Biology Category:Hormones Category:Education